A l3C(∝, n)16O calibration source for KamLAND

We report on the construction and performance of a calibration source for KamLAND using the reaction 13 C(α, n) 16 O with 210 PO as the alpha progenitor. The source provides a direct measurement of this background reaction in our detector, high energy calibration points for the detector energy scale, and data on quenching of the neutron visible energy in KamLAND scintillator. We also discuss the possibility of using the 13 C(α, n) 16 O reaction as a source of tagged slow neutrons.